The present application relates to the video arts. It finds particular application in conjunction with video strobe systems and will be described with particular reference thereto. However, it is to be appreciated, that the present invention will also find application in conjunction with the monitoring of rotating or cyclically repeating constructions.
Heretofore, strobe lights have commonly been used for monitoring rotating, cyclically moving, and randomly moving objects or constructions. Typically, the strobe light includes a high intensity light source which is pulsed very rapidly, typically 10-15 microsecond pulses. The high intensity light is flashed synchronously with the rotation of the construction to be examined. This causes the same portion of the construction to be illuminated in each rotation or cycle. Because only the same segment of the construction is repeatedly illuminated in every revolution or cycle, the viewer, whether the human eye or an opto-electrical device or photographic film, "see" the same segment of the construction in each rotation or cycle as if it were standing still.
The use of strobe lights had several drawbacks. First, the strobe lights required high intensity, 10-15 microsecond light pulses. Few light sources could produce such short pulses. Second, photographic cameras were generally required for making permanent records. Third, because strobe lights tended to interfere with each other, only one could be utilized at a time in a given area. Moreover, strobe lights were not conducive to use with video cameras. A lack of synchronization between the vertical refresh rate and the strobe light led to dark banding and other artifacts in a video image.
The present invention contemplates a new and improved video strobe system which overcomes the above-referenced problems and others.